Happy July 4th! Skip the Gym and Blast Calories on the Beach

Celebrate your independence from the gym tomorrow, and get outdoors for some fresh air! Headed to the beach? You're in luck, says Katie Riley, a San Diego-based personal trainer and Spin instructor at Evolve Health and Fitness: Many of the fun-in-the-sun activities you'd probably be doing anyway are excellent calorie burners, since they use the natural resistance of the sand or the surf to make your body work harder. (But don't worry--you'll be having so much fun you won't even notice!)

We asked Riley to give us her favorite beachside calorie blasters, and her tips for turning each into a stealth workout. Try any of these activities for just half an hour and you'll burn enough to enjoy tomorrow night's cookout guilt-free--with plenty of time left to kick back with a good book and relax.

*Calorie estimates based on a 135-pound woman and 30 minutes of activity.

Beach volleyball: 245 caloriesJust by playing on sand, you’re already burning more than twice the calories you would playing indoors or on grass. No wonder it feels so much harder!

Turn up the burn: Maintain good swimsuit form (abs in tight) throughout the game and while you’re waiting for the ball, hold a squat position to keep those big, high calorie-burning muscles in your legs and lower body working.

Playing Frisbee: 92 calories
A half hour of playing even a casual game of Frisbee burns almost 100 calories, but you can count on significantly more when chasing that disc over loose sand.

Turn up the burn: Go long. Have your partner aim at an imaginary target a few feet away from you to add more running and chasing to the game.

Boogie boarding: 92 calories
If you don’t have one stashed in your garage somewhere, rent a foam boogie board from a beachside sports store. It’ll be just as fun (and heart-pumping!) as you remember it, we promise.

Turn up the burn: Don’t just let the waves carry you in. Sprint towards the shore by kicking your legs as hard as you can. Don’t care who’s watching? Do 10 pushups on the sand before swimming back out for your next wave.

Kadima / paddleball: 184 calories
The equipment for this classic beach game–just two two wooden paddles and a plastic ball–will easily fit in your beach bag.

Turn up the burn: Stand further away from your partner so you’re forced to hit the ball harder, giving your arms more of a workout. Try to keep the volley going as long as possible, running and diving for the ball, as needed. As you wait for return serves, holding a squat can help tone your lower body and torch some extra calories.

Stand-up paddleboarding: 125 – 500 calories
This Hawaiian-inspired sport (also known as SUP) is great exercise for your entire body. While your upper body pulls you through the water, your legs and core muscles work hard to help you stay balanced on the board.

Turn up the burn: Safety is most important, so start off in calm water when you’re first getting the hang of it. As you get more comfortable on the board, you can increase the intensity by paddling more against the wind and over less-calm seas, which will challenge your balance even more, making your muscles work harder to stabilize you.

Brisk walking (or running): 116+ calories
Even if you do nothing else active while you’re there, make it a goal to walk at least 30 minutes up and down the beach at the edge of the water. Cooling your toes in the waves will feel good, and you’ll burn at least enough calories for a cold beer later.

Turn up the burn: You can burn 30% more calories walking–or running–in loose, dry sand as opposed to hard, wet sand or solid ground. Crank up your calorie burn even more by firming up your core and pumping your arms as you walk.

Riding a beach cruiser: 123 calories
Beach cruisers (sturdy bikes built for casual riding on roads and hard sand), can be a fun way to get you from point A to point B–or just a nice way to sightsee around town.

Turn up the burn: Most cruisers don’t have gears you can shift to help you up hills, so your best bet for blasting calories is to take a path with a little bit of incline, providing greater resistance. Sit up nice and tall on the bike, and keep your abs pulled in. Pick up your pace when you can, but remember to watch out for pedestrians! (They’re not always paying attention…)

Inline skating: 337 calories
If your beach has a boardwalk, or even just nearby smoothly-paved streets, strap on a pair of rollerblades for an fun 30-minute workout.

Turn up the burn: Busy beach days can mean a lot of weaving around
pedestrians, but when it’s safe to do so, pick up your speed. The harder you push off and the faster you go, the more calories you’ll burn. Keep your ab muscles engaged; you’ll need them to help you keep your balance. Staying lower to the ground (like a speed skater) and keeping a bend in your knees will keep those leg muscles firing.